The present invention relates to a floppy disk control apparatus for controlling the recording operation for floppy disks having different track densities.
Recently, floppy disk apparatuses have come into widespread use as external storage devices. For example, they are used in personal computers, word processors, etc. In particular, mini floppy disk apparatuses, using 5.25 inch disks and serving as recording media, have been rapidly developed since the apparatus is small and can be widely used in many fields.
There are various kinds of data formats of disks used with mini floppy disk apparatuses. A typical one is set forth in the article, "DISK OPERATING SYSTEM-IBM PERSONAL COMPUTER LANGUAGE SERIES FIRST EDITION", Version 2.00 (January, 1983) pages 0-7. According to the above literature, a file allocation table is prepared in a particular area in the disk, and the format of the disk is identified by the first byte thereof. In the foregoing literature, five kinds of disk formats are defined, and it is disclosed in pages 1 to 10 that only a floppy disk having a track density of 48 TPI (40 tracks per side) can be used.
On the other hand, recently, a mini floppy disk apparatus with a track density of 96 TPI (96 tracks per inch) and a recording ability of 80 tracks per side has been developed based on an improvement in magnetic recording technology. In the mini floppy disk apparatus for driving a 96 TPI disk, during a seeking operation, a magnetic head may travel only half the distance that would be traveled using 96 TPI. Thus, in the mini floppy disk apparatus, when a disk having a track density of 48 TPI is inserted and the reading/writing operations are performed, the magnetic head will have been located, upon the seeking operation, in an intermediate position between tracks. Namely, in the 96 TPI mini floppy disk apparatus, it is impossible to use a 48 TPI disk.